Board drop hammer



'INVENTOR f l i HI June 9,- 1931. H. G. KIMBALL BOARD DROP HAMMER Filed July 15 1926 Patented June 9, 1931 omen s ars;

Miser am cs r :VHARRY KiMBAIIL,OFFBRONXVILLEJNEW YORK, ASSIGNOR TO THE IBILLINGS &

SPENCER C01VI1A1\TY,IOF riAa'rFoR-n, ooiin'nerion'r, A oo'nromvrron or, coni NEGTICUT Application fi1edJ'u1y 15,

I The invention-relates to" improvedjmelans' for controlling the roll frictionin apparatus ofthis kind and more particularly in mul-,

pressure-distributing system, as well as o' :1"; the rolls tl emselves,flexact equalization of pressure acting'on the board has been difiicult to obtain in the first instance, and still more difiicult to maintain under rapid'operation. 7 According to 'the present, invention,

7 '1 r the pressure-distributing system, as. such, 1s

eliminated, and the desired pressure for each set or pair of rolls is obtained by theuse ofia spring orsprings so that it is subject to adjustment and can to the pressure exerted by the other roll-sets,

, or otherwise as desired, and when once adjusted will remain undisturbed by inertia influences,even under thehighest speed oper-- ation, I i t V y p The accompanying drawingsillustrate the principle of the invention, 1'

Figure lshows a front elevation of an ordinary board drop hammer havingxtwo pairs of lifting rolls with thisinvention applied; Figure 2, a larger scale side'elevation'of the roll head thereof, with parts in section 1 and broken out; I v

Figure 3, a plan partly in section of the roll head, and Figure it, a front elevation of the roll head with parts in section. I

The invention may be applied to the ordinary types of board drop hammers, such as that indicated at Fig. 1, which has a base 1,

accordance withthe principle ofthis invention, but only two are shown in the machine taken for illustration,

be made absolutelyequal p a the frlction bar 1 1, orto such other hammer two uprights2 between which the hammer 3 est the hammer f "BOARD" mm HAMM R 1926. Serial 1a. 122,570, s

The front rolls are marked 4; and 5 respec tively and their corresponding rear rolls 1? and 5 and each is fixed on a roll shaft 6;

The two rear rolls may be tomary in this art,that is to say, in eccentric bushings or bearings the head structure and having rearward arms 8, movement of which adjusts the rearrolls toward son of the eccentricity. These arms, at opposite ends of each rearroll, are rigidly j oined" by'crosspins 9 and the two crosspins are cong f nect ed togetherand to an adjustment rod 10,

be adjustably fixed at which is arranged to the back of the machineframe in they usual manner, not shown, so thatthe rear rollscan be simultaneously adjusted asnecessary. I

The lower front roll ings 11, at each end similarto' the bushings 7 and the arms 12 of these bushings are joined rigidly by in-1e is connecteddirectly or indirectly to controlled mechanism as may be employed to control the'reciprocation 0f the hammer, The eccentricbushings 11 are directly mount-'- ed in the head structure and the forward ends of their arms 12 are split to form clamps to hold the cross-pin 18 It will be'apparent that the descent of the friction bar will rock the eccentric bushingsfll so asto move-the. lower" roll 5 toward the hammer board and into frictionallifting engagement therewith. Thelupper front r0114: is also j ournalled in eccentric bushings 15 at each end,-hut these bushings 'are 'themselves journalled in be ar-,

ing. blocks 16, which latter are mounted to move or slide in suitableways formed in the head frame as indicated in vFigure 2, or other-- wise so as to be capable of movementtransverselyto the plane of the hammer board. The detail design of the bearing blocks and their guiding means is of course subject to" variation Each block is normally pressed toward the end of its path orslide-way, near-, board, by a strongspring 17, which can be adjusted .bylthe screw 18 actingon thespring thro I The actuating arms 19 of the eccentric bushcross-pin 13, and this crossjournalled as cus- 7, mountedjdirectly in v and from the hammer board by ,rea-

5 is journalled, by 1 its roll 'shaftin ec'centric'bushings or bearughafollo-wer plate18a; 1G0

V In its ascent the stud 24 on the hammer enings are rigidly joined together by a crosspin 20, clamped in their split ends, and connected by a link 21 with the cross-pin 13 of thelower front roll, or otherwise connected to the friction bar so that when the" latter falls, both arms19and 12 are thereby rocked downwardly. This movement moves the upper front roll as well as the lower roll toward the hammer board. The innermost position of the bearing blocks 16, in their slideways,

is such that the axis of the upper front roll bushings is at the same distance from the board as that of the lower front roll bushings,

so that when the friction bar drops both rolls engage the board simultaneously. The pres sure which can be exerted by the upper roll upon the board is obviously limited by the adjustment of the springs 17 and on any pressure in' excess of the limit so imposed,

thebearing'blocks 16 yield, compressing the springs. The spring adjustment is made to equal the pressure which the lower roll exerts on the board so that the pressures on both rolls aresubstantially equalized. The movementof the bearing blocks themselves is so slight that on the lifting of the friction bar the rolls withdraw from the hammer bar simultaneously and positively and thus neither can drag on the board to impair its uniform friction surface. Obviously the yielding roll mounting above described can be designed in various ways and associated with other means than the particular eccentric bushings'15 for moving the roll relatively to the mounting; obviously aweight or weights can be used in place of the springs,

and obviously also, the principle described can be applied to both pairs of rolls or to more than two pairs.

- It will be understood that the lower end of the friction bar-is guided in a knockoff box 22, which is is conventionally shown in the drawings and which contains a catch adapted tohold the friction bar in an elevated position when it has been lifted by the hammer. This catch is released by a cam face on the hammer when the latter falls, thereby letting the'friction bar fall, which causes the lifting rolls to grip the board and lift the hammer.

gages alever 25 fastened to the friction bar and raises the-latter until it is again sus- I tained by the catch. The lifting of the fricfixed to theextended end of the rear shaft 6; the two lower rolls are similarly geared gethe by gea fifl n dr ven by the, bel

pulley 31 on the rear shaft at the oppositeside of the machine.

I claim: 7

1. In a multiple roll-set, board drop-hammer, the combination of one rollof one of the pairs of rolls, a yielding mounting therefor, hammer-controlled means for moving said roll, relatively to said yielding mounting, toward and from the hammer board, and a roll of another pair also moved by said means.

2. In a multiple roll-set, board drop-hammer, the combination of one roll of one of the pairs of rolls, a yielding mounting therefor, means for urging the mounting toward the board, hammer-controlled means for moving said roll relatively to said yielding mounting, and a roll of another pair also moved by said means. 7

3, In a multiple rollset, board drop-hammer, the combination of one roll of one of the pairs of rolls, a yielding mounting therefor, means urging said mounting inwardly against a fixed inward limit or abutment, hammer-controlled means for moving said roll in both. directions relatively to said yielding mounting, and a roll of another pair also moved by said means; i V

4:. In a board drop hammer, a plurality of pairs of lifting rolls, a yielding roll mounting for one of the rolls of one of the pairs of rolls, means urging said mounting toward the board, an actuating arm for moving the axis of said roll relatively to said mounting, an actuating arm for one of the rolls of another pair of rolls, a rigid connection between said arms, and hammer controlled mechanism for moving said arms.

5. In a board drop hammer, a plurality of pairs of lifting rolls, a yielding roll mounting for one of the rolls of one of the roll sets comprising bearing blocks having ways in which they may yield away from the hammer board, springs normally holding said blocks at the inward limits of their ways, a lifting roll carried by said blocks, another lifting roll and hammer-controlled moving the axes of both rolls with reference to the board. I

In testimonywhereof, I have signed this specification.

HARRY G. KIMBALL.

mechanism for 

